- One uncontrolled study of 35 men with low sperm counts.[1]
- Reported improvements in sperm count, motility and testosterone.
- No placebo group, so the cause is uncertain.
- No study measured pregnancies; rated “Very limited”.
Evidence at a glance
One uncontrolled before-and-after study in men with low sperm counts. How ratings work: evidence rating system.
The study in detail
| Feature | Detail |
|---|---|
| Participants | 35 men with low sperm counts (oligospermia)[1] |
| Design | Before-and-after; no placebo group |
| Duration | About 90 days |
| Reported | Improvements in sperm count, motility and testosterone |
| Not measured | Pregnancy or live birth rates |
Why the result is uncertain
Without a placebo group, a before-and-after study can’t separate a supplement’s effect from other explanations. Sperm counts vary naturally from one sample to the next, and men with unusually low counts at the start often show higher counts later simply by chance, an effect known as regression to the mean. Lifestyle changes made at the same time can also play a part. That is why this study rates “Very limited” despite its positive findings; see why one study doesn’t prove a claim.
Why trial length matters
Sperm take roughly three months to develop, so a fertility study needs to run for at least that long to capture a full cycle. The roughly 90-day length of this study was appropriate for that reason. A future controlled trial would need a similar or longer duration, a placebo group, and ideally pregnancy outcomes.
The testosterone connection
Separately, a randomised trial in healthy men aged 45–55 reported higher testosterone than placebo.[2] Testosterone is involved in sperm production, but higher levels in healthy men don’t show improved fertility, and men with fertility problems weren’t studied in that trial. See testosterone.
If you are trying to conceive
- See a GP if you’ve been trying for a yearSooner if the woman is over 35 or there are known concerns.
- Get a semen analysisIt is a simple, standard first test.
- Address lifestyle factorsSmoking, alcohol, weight and heat exposure all affect sperm.
- Discuss supplements with your clinicIncluding shilajit, if you’re considering it.
Safety for couples trying to conceive
Contaminants matter when trying to conceive, because metals such as lead can affect reproductive health and vary between shilajit batches.[3] If you choose to take shilajit, use a product with a batch report showing metals within GB limits.[4] Partners who may become pregnant shouldn’t take shilajit; see pregnancy and breastfeeding.
Fertility claims and UK rules
“Supports male fertility” is a health claim that needs authorised wording in UK marketing.[5][6] Some nutrients, such as zinc and selenium, have authorised claims about normal fertility or sperm formation; shilajit doesn’t. Claims to treat infertility are medicinal claims.[7]
What a convincing fertility trial would need
A trial capable of supporting a fertility claim would randomly assign men with low sperm counts to shilajit or placebo for at least three months, use standard semen analysis at the start and end, and ideally follow couples to see whether pregnancy rates differ. It would also report the product used and its contaminant results. No such trial has been published for shilajit, so the evidence stays “Very limited”.
What improves sperm health
Stopping smoking, limiting alcohol, reaching a healthy weight, avoiding overheating of the testicles, and staying active are all associated with better sperm health. Some medicines and anabolic steroids can seriously reduce sperm production, so it is worth reviewing these with a GP.
Age and male fertility
Sperm quality tends to decline gradually with age. That makes timely assessment more useful than waiting to see whether a supplement helps, especially if the female partner is also older.
If you decide to try shilajit
Use a product with a batch report showing metals within GB limits, follow the label serving, and tell your fertility clinic. Keep a note of the batch number.
The bottom line
One uncontrolled study suggests sperm measures may improve with shilajit, but without a placebo group, the effect is uncertain, and pregnancy wasn’t measured. Couples trying to conceive will get far more from a fertility assessment and lifestyle changes than from a supplement with this level of evidence.
Frequently asked questions
Does shilajit increase sperm count?
One uncontrolled study of 35 men reported improvements, but without a placebo group the cause is uncertain.[1]
Does shilajit improve sperm motility?
The same study reported improved motility, with the same limitation.[1]
Can shilajit help couples get pregnant?
Pregnancy rates haven’t been measured in any shilajit study.
How long would shilajit take to affect sperm?
Sperm take about three months to develop; the study lasted about 90 days.[1]
Should I take shilajit before IVF?
Discuss all supplements with your fertility clinic first.
Is shilajit safe for my partner if we’re trying to conceive?
Partners who may become pregnant shouldn’t take shilajit, as it hasn’t been studied in pregnancy.
Which nutrients have authorised fertility claims?
Some, such as zinc and selenium, have authorised claims related to normal fertility or sperm formation.[5]
What is regression to the mean?
The tendency for unusually low or high measurements to move closer to average when measured again, even without treatment.
When should we seek fertility help?
After a year of trying, or sooner if the woman is over 35 or there are known concerns.
Can heavy metals affect fertility?
Metals such as lead can affect reproductive health, which is why batch testing matters.[3]
Sources & further reading
Primary research, regulators and standards bodies are cited first. A source being listed here does not mean it supports every claim made by sellers; it supports the specific statement it is attached to.
- Biswas TK, Pandit S, Mondal S, et al.. Clinical evaluation of spermatogenic activity of processed Shilajit in oligospermia. Andrologia 42(1):48–56, 2010. PMID 20078516. View source (opens in a new tab) [Uncontrolled clinical study]
- Pandit S, Biswas S, Jana U, De RK, Mukhopadhyay SC, Biswas TK. Clinical evaluation of purified Shilajit on testosterone levels in healthy volunteers. Andrologia 48(5):570–575, 2016. PMID 26395129. View source (opens in a new tab) [Randomised controlled trial]
- Quantifying of thallium in Shilajit and its supplements to unveil the potential risk of consumption of this popular traditional medicine. BMC Chemistry 19:20, 2025. doi:10.1186/s13065-025-01384-7. View source (opens in a new tab) [Laboratory analysis]
- European Commission (UK version on legislation.gov.uk). Commission Regulation (EC) No 629/2008 amending Regulation (EC) No 1881/2006 setting maximum levels for certain contaminants in foodstuffs. legislation.gov.uk, 2008. View source (opens in a new tab) [UK legislation (retained)]
- Department of Health and Social Care. Great Britain nutrition and health claims (NHC) register. GOV.UK. View source (opens in a new tab) [Official register]
- Committee of Advertising Practice. UK Code of Non-broadcast Advertising (CAP Code), Section 15: Food, food supplements and associated health or nutritional claims. asa.org.uk. View source (opens in a new tab) [Advertising code]
- Medicines and Healthcare products Regulatory Agency. Borderline products: how to tell if your product is a medicine. GOV.UK. View source (opens in a new tab) [Regulator guidance]